Deposition and treatment of TiO2 as an alternative for ultrathin gate dielectrics

We investigated the use of TiO2 as an alternate gate dielectric for future CMOS applications. To reduce the leakage current, different post deposition treatments were investigated. It was found that for very thin TiO2 films, ozone plasma exposure is an effective way in lowering thermal budget of the post deposition annealing. Doping TiO2 with Si and/or Al can also be effective in substantially reducing the leakage current. in addition, the doped TiO2 has the desirable property of remaining amorphous even after anneal at 850 degrees C. We also report the fabrication of submicron MOSFETs with TiO2 gate dielectrics equivalent to 2 nm of SiO2 and TiN/Cu gate electrodes.